Laser Trabeculoplasty for Glaucoma ALT vs SLT Animation
Trabeculoplasty is a laser treatment for primaryopenangle glaucoma. The laser is used to treat the trabecular meshwork, through whichthe aqueous humor drains. In this procedure: The eye is numbed with eye drops. A special laser lens is placed on the eye to help control the direction of the laserbeams. The laser burns a small area in the trabecularmeshwork, opening up the drainage canal. About 50 spots over 180 degrees of the meshworkcircle are treated in one therapy. The original laser trabeculoplasty procedureapplies argon laser of 514nm wavelength on half of the meshwork circle in one treatment.Although a second treatment can be performed
on the other half of the circle, the procedureis generally not repeatable as it causes extensive scarring of the trabecular meshwork.The newer technique Selective Laser Trabeculoplasty or SLT uses a solidstate laser of 532nmwavelength. The pulse energy of SLT is about 100 times lower than the traditional argonlaser trabeculoplasty. SLT selectively targets pigmented cells while leaving the rest ofthe trabecular meshwork tissue intact. For this reason, it can be applied to 360 degrees of the meshwork in one treatment and is considered safe to be repeated.In term of efficiency, the two techniques return similar results in lowering intraocularpressure. Laser trabeculoplasty treatment
is effective in about 75% of patients. Theeffect may take a few weeks to kick in and can last for several years.